Altered Resting-State Co-Activation Patterns in Obsessive-Compulsive Disorder.

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Obsessive-compulsive disorder (OCD) is associated with abnormal large-scale brain network dynamics.
• Transient whole-brain co-activation states in OCD are not well understood.
• This study investigates alterations in whole-brain co-activation pattern (CAP) dynamics in OCD.

Purpose of the Study:

• To characterize the dynamics of whole-brain co-activation patterns (CAPs) in individuals with OCD.
• To compare CAP dynamics between patients with OCD and healthy controls.
• To identify specific alterations in brain state transitions associated with OCD.

Main Methods:

• Resting-state functional magnetic resonance imaging (rs-fMRI) data were analyzed using a CAP framework with the Brainnetome 246 atlas.
• Co-activation pattern (CAP) states were identified using k-means clustering.
• Temporal fraction, persistence, counts, and transition probabilities of CAP states were compared between OCD patients and healthy controls.

Main Results:

• Three recurrent CAP states were identified, with CAP2 showing a distinct intermediate bipolar configuration involving default mode and somatomotor systems.
• Patients with OCD demonstrated increased temporal fraction, persistence, and self-transition probability of CAP2 compared to controls.
• OCD patients exhibited reduced counts and decreased transition probabilities from CAP2 to other states (CAP1 and CAP3).

Conclusions:

• Obsessive-compulsive disorder is characterized by altered brain network dynamics, specifically reduced switching flexibility.
• Individuals with OCD show an increased tendency to remain in a particular brain state configuration over time.
• These findings highlight the role of aberrant brain state dynamics in the pathophysiology of OCD.